The present invention relates to braking of a vehicle, and in particular to a brake system of a vehicle.
Vehicles currently have brake systems that are used to inhibit rotation of the wheels of the vehicle to decelerate and stop the vehicles. The brake systems of vehicles typically include a hydraulic brake system having disc brakes and/or drum brakes. The disc brakes include a brake pad that engages a rotor interconnected to the tire of the vehicle to decelerate the vehicle. The drum brakes include brake shoes that engage a drum interconnected to the tire of the vehicle to decelerate the vehicle.
Heretofore, vehicles having a hydraulic brake system have experienced brake torque variation due to disc thickness variation (DTV) in the rotor of disc brakes or insufficient cylindricity of the drum in drum brakes. The forces created by the brake torque variation are transmitted to the tire of the vehicle and cause the tires of the vehicle to vibrate in the longitudinal direction of the tire. This vibration is thereafter transmitted to the brake system and chassis of the vehicle and results in brake roughness. Brake roughness is defined as the unexpected vibration that the driver of the vehicle feels through the steering wheel, brake pedal and seat track. The vibration associated with brake roughness can be transmitted to the driver of the vehicle, causing the driver to feel the vibrations. FIG. 4 shows the brake torque of a vehicle using the prior art rotor with a DTV less than 6 microns as a function of time during a simulated stop on a brake dynamometer. As seen in FIG. 4, the prior art hydraulic brake system with a DTV less than 6 microns does not experience significant brake torque variation. However, as seen in FIG. 5, when the DTV of the prior art rotor is 30 microns, the brake torque variation can become significant.
Accordingly, a practical, economical braking system reducing brake torque variation and brake roughness is desired.
An aspect of the present invention is to provide a brake system for a vehicle having wheels. The brake system includes a brake housing and a flow chamber housing. The brake housing includes a friction element being adapted to move to engage a portion of the wheels to inhibit rotation of the wheels. The flow chamber housing includes an enlarged flow chamber having a peripheral wall and a pair of oppositely facing walls. The a substantially circular flow chamber and a brake fluid line. The substantially circular flow chamber has a circumferential wall andenlarged flow chamber is fluidly interconnected to the brake housing for supplying fluid to the brake housing for moving the friction element. The brake fluid line is connected substantially The flow chamber housing includes a first fluid line connected to the tangentially to the circumferential wall of the substantially circular flow chamber whereby aperipheral wall of the enlarged flow chamber and a master cylinder fluid line connected to one of the pair of oppositely facing walls of the enlarged flow chamber. A pressure wave in the fluid entering the substantially circularenlarged flow chamber from the firstfirst fluid line will be forced to move in a substantially circular pathreflect off of the peripheral wall at a plurality of points to thereby dissipate the pressure wave.
Another aspect of the present invention is to provide a vehicle having a wheel, a brake housing, a master cylinder and a flow chamber housing. The brake housing is located adjacent the wheel. The brake housing includes a friction element adapted to move to engage a portion of the wheel to inhibit rotation of the wheel. The master cylinder is adapted to provide a force to a brake fluid in the brake housing to move the friction element. The flow chamber housing is located in a fluid path between the brake housing and the master cylinder. The flow chamber housing includes a substantially circular flow chamber having a circumferential wall, a first fluid line fluidly connected to the brake housing and a second fluid line fluidly connected to the master cylinder. The first fluid line is connected substantially tangentially to the circumferential wall of the substantially circular flow chamber whereby a pressure wave in the fluid entering the substantially circular flow chamber from the first fluid line will be forced to move in a substantially circular path to thereby dissipate the pressure wave.
Yet another aspect of the present invention is to provide a fluid system adapted to be connected to a braking system of a vehicle for dissipating a pressure wave in a fluid coming from the braking system. The fluid system includes a substantially circular flow chamber, a first fluid line and a second fluid line. The substantially circular flow chamber has a circumferential wall, with the substantially circular flow chamber being adapted to contain the fluid. The first fluid line is connected to the substantially circular flow chamber. The first fluid line is adapted to allow the pressure wave in the fluid to enter into the substantially circular flow chamber. The second fluid line is also connected to the substantially circular flow chamber. The second fluid line is adapted to be fluidly connected to a master cylinder of the braking system. The first fluid line is connected substantially tangentially to the circumferential wall of the substantially circular flow chamber whereby the pressure wave entering the substantially circular flow chamber from the first fluid line will be forced to move in a substantially circular path to thereby dissipate the pressure wave.
The fluid system and the brake system of the vehicle are efficient in use, economical to install, capable of a long operable life, and particularly adapted for the proposed use.
These and other features, advantages, and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings.